1. Technical Field
The present invention relates in general to the excavation of earth, and in particular for extracting remnant material from a trench and remnant material which is proximate to the trench. Still more particularly, the present invention relates to an apparatus for grooming a trench after the trench has been cut.
2. Description of the Related Art
Creating trenches for underground utilities such as water, sewer, and electricity is a multi-billion dollar industry. Historically, a considerable amount of human labor has been required to dig trenches and prepare trenches for the insertion of conduit or wires. Cutting, grooming and back-filling trenches is a construction process which presently requires a significant amount of manual labor. Due to the high cost of manual labor, a competitive industry for mechanized trenching equipment has evolved. The quest to minimize manual labor in preparing trenches has created significant competition in the trenching machinery industry.
After a trench has been cut into the earth, the crumbs or remnant material typically remains at the bottom of the trench and at the mouth of the trench. Grooming the bottom of the trench to remove crumbs before placement of conduit or electrical wire nearly always requires manual labor. This process is often called "crumbing" the trench. For many applications such as septic field excavation, the bottom of the trench must be homogenous or the bottom of the trench must not have high and low areas. If a trench is narrow and deep such that an individual cannot stand in the trench, a considerable amount of manual labor is required to groom the trench.
Referring to FIG. 1, a cross-sectional illustration of a furrow or trench 10 is depicted. In the lower portion of trench 10, crumbs 18 reside which were never fully extracted from trench 10 or have fallen into trench 10. Additionally, crumbs at ground level 12 reside beside the mouth of trench 10. Sidewalls 16 of trench 10 are comprised of undisturbed soil or rock.
A typical trenching operation must comply with a written specification for the specific application. Generally, a trench specification is based upon the composition of the earth and what will be placed in the trench. For example, field tile and/or leach lines of a septic system require the bottom of the trench to be level such that when the conduit is placed into the trench it is linear. Laying the conduit over undulations or high spots and low spots can create serious malfunctions in the performance of a drainage system.
Further, certain trench specifications require the back-fill material to be of a specific nature, such as sand. When the back-fill material is to be a foreign material such as sand or concrete, substantially all surface crumbs 14 at ground level 12 above trench 10 as well as crumbs 18 in the bottom of trench 10 must be removed from the excavation area.
Attempting to remove crumbs from the top of trench 10 is very tedious because a loader bucket or blade will push surface crumbs 14 at the top of trench 10 into the bottom of trench 10. Many attempts have been made to enhance the cleaning capabilities of trenching machinery. For example, a member called a "crumber" has been placed at the end of the chain or conveyor on trenchers to pull the crumbs along and feed the crumbs back into the trenching chain for extraction from the trench.
Crumbers provide less than satisfactory results because crumbs on top of the trench typically fall back into the trench after the trenching machine has passed. Crumbers are also ineffective if the crumbs at the top of the trench are to be removed.
Conveyor belt arrangements have been utilized to convey crumbs further from the mouth of the trench. However, for implementation of a septic field parallel trenches are spaced only a few feet apart and conveyors either dump crumbs into an existing trench or leave the soil uneven on an area which is yet to be trenched. A conveyor for carrying spoils away from the trench is unsuited for many trenching applications.
It would therefore be desirable to provide an apparatus to clean crumbs proximate to a trench. It would be advantageous to provide an apparatus for simultaneously cleaning the bottom of a trench and the mouth of the trench.